/usr/share/gocode/src/github.com/hashicorp/raft/peer.go is in golang-github-hashicorp-raft-dev 0.0~git20160317.0.3359516-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 | package raft
import (
"bytes"
"encoding/json"
"io/ioutil"
"os"
"path/filepath"
"sync"
)
const (
jsonPeerPath = "peers.json"
)
// PeerStore provides an interface for persistent storage and
// retrieval of peers. We use a separate interface than StableStore
// since the peers may need to be edited by a human operator. For example,
// in a two node cluster, the failure of either node requires human intervention
// since consensus is impossible.
type PeerStore interface {
// Peers returns the list of known peers.
Peers() ([]string, error)
// SetPeers sets the list of known peers. This is invoked when a peer is
// added or removed.
SetPeers([]string) error
}
// StaticPeers is used to provide a static list of peers.
type StaticPeers struct {
StaticPeers []string
l sync.Mutex
}
// Peers implements the PeerStore interface.
func (s *StaticPeers) Peers() ([]string, error) {
s.l.Lock()
peers := s.StaticPeers
s.l.Unlock()
return peers, nil
}
// SetPeers implements the PeerStore interface.
func (s *StaticPeers) SetPeers(p []string) error {
s.l.Lock()
s.StaticPeers = p
s.l.Unlock()
return nil
}
// JSONPeers is used to provide peer persistence on disk in the form
// of a JSON file. This allows human operators to manipulate the file.
type JSONPeers struct {
l sync.Mutex
path string
trans Transport
}
// NewJSONPeers creates a new JSONPeers store. Requires a transport
// to handle the serialization of network addresses.
func NewJSONPeers(base string, trans Transport) *JSONPeers {
path := filepath.Join(base, jsonPeerPath)
store := &JSONPeers{
path: path,
trans: trans,
}
return store
}
// Peers implements the PeerStore interface.
func (j *JSONPeers) Peers() ([]string, error) {
j.l.Lock()
defer j.l.Unlock()
// Read the file
buf, err := ioutil.ReadFile(j.path)
if err != nil && !os.IsNotExist(err) {
return nil, err
}
// Check for no peers
if len(buf) == 0 {
return nil, nil
}
// Decode the peers
var peerSet []string
dec := json.NewDecoder(bytes.NewReader(buf))
if err := dec.Decode(&peerSet); err != nil {
return nil, err
}
// Deserialize each peer
var peers []string
for _, p := range peerSet {
peers = append(peers, j.trans.DecodePeer([]byte(p)))
}
return peers, nil
}
// SetPeers implements the PeerStore interface.
func (j *JSONPeers) SetPeers(peers []string) error {
j.l.Lock()
defer j.l.Unlock()
// Encode each peer
var peerSet []string
for _, p := range peers {
peerSet = append(peerSet, string(j.trans.EncodePeer(p)))
}
// Convert to JSON
var buf bytes.Buffer
enc := json.NewEncoder(&buf)
if err := enc.Encode(peerSet); err != nil {
return err
}
// Write out as JSON
return ioutil.WriteFile(j.path, buf.Bytes(), 0755)
}
|